1. Field of the Invention
The present invention relates to internal combustion powerplants, and more particularly to swash plate articulated engines conformed for opposed piston reciprocation.
2. Description of the Prior Art
An internal combustion engine derives its power from the volumetric compression of a gas mixture prior to its ignition. This volumetric change is most often effected by reciprocating pistons which in the course of each stroke vary the gas volume captured in a cylinder. The reciprocal piston motion thus effects the gas compression and also the intake of the next gas charge and its exhaust following ignition.
Heretofore, it has been the prevailing practice to tie the pistons to a rotary crankshaft in order to convert the reciprocal power into rotation. The automotive engine is a prime example of this approach, now reaching the limits of its full development. Crank articulated powerplants, however, entail inherent characteristics of the cranck mechanism associated with the required connecting rod, which result in lateral force components resolved at the piston to cylinder wall interface. Also associated with the cranck mechanism are the centrifugal loads of the rod end tied to the crank, and the connecting rod bending modes compounded by the crank dynamics. These have combined to limit the shaft rotation rate, thus limiting the power levels of the engine. The power to weight density is therefore approaching its inherent limits.
In the past an alternative form of an internal combustion engine has been devised, generally based on a swash or wobble plate mounted on a rotary shaft. Examples of such a power plant may be found in the teachings of U.S. Pat. Nos. 3,521,614 to Orkney; 1,613,116 to Michell; 1,885,323 to Duryea; and 1,407,047 to Trowbridge. In the engine structure of this type the displacement of the swash plate edge is connected to the reciprocal motion of the piston, thus converting directly the expansion of the ignited charge into shaft rotation. This particular mechanism obtains extensive simplifications in the component dynamics, eliminating the compound kinematic effects associated with cranck motion.
More importantly, the elimination of many of the lateral load components simplifies the piston to cylinder interface, allowing close tolerances therebetween to minimise parasitic losses that now entail complex sealing. A swash plate mechanism, therefore, obtains many advantages, and it is the improvement of this mechanism that is disclosed herein.